'\" te
.\"  Copyright (c) 1999, Sun Microsystems, Inc.  All Rights Reserved
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.TH ECONVERT 3C "April 9, 2016"
.SH NAME
econvert, fconvert, gconvert, seconvert, sfconvert, sgconvert, qeconvert,
qfconvert, qgconvert \- output conversion
.SH SYNOPSIS
.LP
.nf
#include <floatingpoint.h>

\fBchar *\fR\fBeconvert\fR(\fBdouble\fR \fIvalue\fR, \fBint\fR \fIndigit\fR, \fBint *\fR\fIdecpt\fR, \fBint *\fR\fIsign\fR,
     \fBchar *\fR\fIbuf\fR);
.fi

.LP
.nf
\fBchar *\fR\fBfconvert\fR(\fBdouble\fR \fIvalue\fR, \fBint\fR \fIndigit\fR, \fBint *\fR\fIdecpt\fR, \fBint *\fR\fIsign\fR,
     \fBchar *\fR\fIbuf\fR);
.fi

.LP
.nf
\fBchar *\fR\fBgconvert\fR(\fBdouble\fR \fIvalue\fR, \fBint\fR \fIndigit\fR, \fBint\fR \fItrailing\fR, \fBchar *\fR\fIbuf\fR);
.fi

.LP
.nf
\fBchar *\fR\fBseconvert\fR(\fBsingle *\fR\fIvalue\fR, \fBint\fR \fIndigit\fR, \fBint *\fR\fIdecpt\fR, \fBint *\fR\fIsign\fR,
     \fBchar *\fR\fIbuf\fR);
.fi

.LP
.nf
\fBchar *\fR\fBsfconvert\fR(\fBsingle *\fR\fIvalue\fR, \fBint\fR \fIndigit\fR, \fBint *\fR\fIdecpt\fR, \fBint *\fR\fIsign\fR,
     \fBchar *\fR\fIbuf\fR);
.fi

.LP
.nf
\fBchar *\fR\fBsgconvert\fR(\fBsingle *\fR\fIvalue\fR, \fBint\fR \fIndigit\fR, \fBint\fR \fItrailing\fR, \fBchar *\fR\fIbuf\fR);
.fi

.LP
.nf
\fBchar *\fR\fBqeconvert\fR(\fBquadruple *\fR\fIvalue\fR, \fBint\fR \fIndigit\fR, \fBint *\fR\fIdecpt\fR, \fBint *\fR\fIsign\fR,
     \fBchar *\fR\fIbuf\fR);
.fi

.LP
.nf
\fBchar *\fR\fBqfconvert\fR(\fBquadruple *\fR\fIvalue\fR, \fBint\fR \fIndigit\fR, \fBint *\fR\fIdecpt\fR, \fBint *\fR\fIsign\fR
     \fBchar *\fR\fIbuf\fR);
.fi

.LP
.nf
\fBchar *\fR\fBqgconvert\fR(\fBquadruple *\fR\fIvalue\fR, \fBint\fR \fIndigit\fR, \fBint\fR \fItrailing\fR, \fBchar *\fR\fIbuf\fR);
.fi

.SH DESCRIPTION
.LP
The \fBeconvert()\fR function converts the \fIvalue\fR to a null-terminated
string of \fIndigit\fR \fBASCII\fR digits in \fIbuf\fR and returns a pointer to
\fIbuf\fR. \fIbuf\fR should contain at least \fIndigit+1\fR characters. The
position of the decimal point relative to the beginning of the string is stored
indirectly through \fIdecpt\fR. Thus \fIbuf\fR == "314" and \fI*decpt\fR == 1
corresponds to the numerical value 3.14, while \fIbuf\fR == "314" and
\fI*decpt\fR == \(mi1 corresponds to the numerical value .0314. If the sign of
the result is negative, the word pointed to by \fIsign\fR is nonzero; otherwise
it is zero. The least significant digit is rounded.
.sp
.LP
The \fBfconvert()\fR function works much like \fBeconvert()\fR, except that the
correct digit has been rounded as if for  \fBsprintf(%w.nf)\fR output with
\fIn\fR=\fIndigit\fR digits to the right of the decimal point. \fIndigit\fR can
be negative to indicate rounding to the left of the decimal point. The return
value is a pointer to \fIbuf\fR. \fIbuf\fR should contain at least
\fI310+max(0,ndigit)\fR characters to accommodate any double-precision
\fIvalue\fR.
.sp
.LP
The \fBgconvert()\fR function converts the \fIvalue\fR to a null-terminated
\fBASCII\fR string in \fIbuf\fR and returns a pointer to \fIbuf\fR. It produces
\fIndigit\fR significant digits in fixed-decimal format, like
\fBsprintf(%w.nf)\fR, if possible, and otherwise in floating-decimal format,
like  \fBsprintf(%w.ne)\fR; in either case \fIbuf\fR is ready for printing,
with sign and exponent. The result corresponds to that obtained by
.sp
.in +2
.nf
(void) sprintf(buf,``%w.ng'',value) ;
.fi
.in -2

.sp
.LP
If \fItrailing\fR = 0, trailing zeros and a trailing point are suppressed, as
in  \fBsprintf(%g)\fR. If \fItrailing\fR != 0, trailing zeros and a trailing
point are retained, as in  \fBsprintf(%#g)\fR.
.sp
.LP
The \fBseconvert()\fR, \fBsfconvert()\fR, and \fBsgconvert()\fR functions are
single-precision versions of these functions, and are more efficient than the
corresponding double-precision versions. A pointer rather than the value itself
is passed to avoid C's usual conversion of single-precision arguments to
double.
.sp
.LP
The \fBqeconvert()\fR, \fBqfconvert()\fR, and \fBqgconvert()\fR functions are
quadruple-precision versions of these functions. The \fBqfconvert()\fR function
can overflow the  \fIdecimal_record\fR field  \fIds\fR if \fIvalue\fR is too
large. In that case, \fIbuf\fR[0] is set to zero.
.sp
.LP
The \fBecvt()\fR, \fBfcvt()\fR and \fBgcvt()\fR functions are versions of
\fBeconvert()\fR, \fBfconvert()\fR, and \fBgconvert()\fR, respectively, that
are documented on the \fBecvt\fR(3C) manual page.  They constitute the default
implementation of these functions and conform to the X/Open CAE Specification,
System Interfaces and Headers, Issue 4, Version 2.
.SH USAGE
.LP
\fBIEEE\fR Infinities and NaNs are treated similarly by these functions.
``NaN'' is returned for NaN, and ``Inf'' or ``Infinity'' for Infinity.  The
longer form is produced when \fIndigit\fR >= 8.
.SH ATTRIBUTES
.LP
See \fBattributes\fR(7) for descriptions of the following attributes:
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
MT-Level	MT-Safe
.TE

.SH SEE ALSO
.LP
.BR ecvt (3C),
.BR sprintf (3C),
.BR attributes (7)
